Overview

Syphilis is a sexually transmitted infection caused by the spirochete bacterium Treponema pallidum subspecies pallidum. The primary route of transmission is through sexual contact; it may also be transmitted from mother to fetus during pregnancy or at birth, resulting in congenital syphilis. The exact origin of syphilis is disputed. Syphilis was indisputably present in the Americas before European contact. The dispute is over whether or not syphilis was also present elsewhere in the world at that time. The causative organism, Treponema pallidum, was first identified by Fritz Schaudinn and Erich Hoffmann in 1905.